Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS5978890 A
Publication typeGrant
Application numberUS 08/779,471
Publication dateNov 2, 1999
Filing dateJan 8, 1997
Priority dateJan 10, 1996
Fee statusPaid
Also published asDE69731323D1, DE69731323T2, EP0784260A1, EP0784260B1, EP1333371A2, EP1333371A3, US6321292, US6470432, US20020032834, USRE43600
Publication number08779471, 779471, US 5978890 A, US 5978890A, US-A-5978890, US5978890 A, US5978890A
InventorsKoji Ozawa, Kazuhide Sano, Takeshi Koide, Katsunori Nakamura
Original AssigneeHitachi, Ltd.
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
External storage control device and data transfer method between external storage control devices
US 5978890 A
Abstract
In a data processing system in which main and sub disk storage devices are under the control of individual each disk control devices, the write processing time is reduced by selectively sending data according to the command-chaining time between main and sub disk control devices. A section for judging cable length and function of the sub disk control device 36 estimates command-chaining time between a pair of main and sub disk storage devices. The channel command analyzing section 31 estimates the number of records to be transferred and the length of a record using a LOCATE RECORD command. The command judgment section for the sub disk control device 32 optimizes the command-chain to be issued to the sub disk control device using the above-mentioned information. Then, the section for issuing command to the sub disk control device 35 issues the optimized command chain. Thus, a shorter transmission time is realized by either sending individual records or an entire track of data.
Images(6)
Previous page
Next page
Claims(25)
What is claimed is:
1. A system comprising:
a host processor;
a plurality of external storage devices connected to the host processor; and
means for transferring data from the host processor to one of said plurality of external storage devices by comparing a first transfer time for sending an entire track of data and a second transfer time for sending a specified number of individual records,
wherein the calculation of the first and second transfer times includes a determination of command chain time for sending data from the host processor and receiving a response from said one of said plurality of external storage devices,
wherein said means for transferring data transfers data according to a shorter of the first and second transfer times;
wherein the command chain time determination depends upon a distance between the host processor and said one of said plurality of external storage devices; and
wherein said distance is calculated and stored in a memory.
2. A system comprising:
a host processor;
a plurality of external storage devices connected to the host processor; and
means for transferring data from the host processor to one of said plurality of external storage devices by comparing a first transfer time for sending an entire track of data and a second transfer time for sending a specified number of individual records,
wherein the calculation of the first and second transfer times includes a determination of command chain time for sending data from the host processor and receiving a response from said one of said plurality of external storage devices,
wherein said means for transferring data transfers data according to a shorter of the first and second transfer times; and
wherein the plurality of external storage devices are serially connected to said host processor such that only one of the external storage devices is directly connected to the host processor and remaining ones of the external storage devices are connected to the host processor through one or more of the external storage devices.
3. A system comprising:
a host processor;
an external storage device connected to the host processor; and
means for transferring data from the host processor to said external storage device by comparing a first transfer time resulting from sending an entire track of data and a second transfer time resulting from sending a specified number of individual records,
wherein the calculation of the first and second transfer time includes a determination of command chain time for sending data from the host processor and receiving a response from said external storage device,
wherein said means for transferring data transfers data according to a shorter of the first and second transfer times;
wherein the command chain time determination depends upon a distance between the host processor and said external storage device; and
wherein said distance is calculated and stored in a memory.
4. A system comprising:
a host processor;
a plurality of external storage devices connected to the host processor; and
means for transferring data from the host processor to one of said plurality of external storage devices by comparing a first transfer time for sending an entire track of data and a second transfer time for sending a specified number of individual records,
wherein the calculation of the first and second transfer times includes a determination of command chain time for sending data from the host processor and receiving a response from said one of said plurality of external storage devices,
wherein said means for transferring data transfers data according to a shorter of the first and second transfer times; and
wherein the calculation of the first and second transfer times includes a determination of the length of the data to be sent as well as the system transfer time.
5. A system according to claim 4, wherein the calculation of the second transfer time includes a determination of the number of records to be sent.
6. A first external storage control device which is connected to a first group of external storage devices and controls data transfer between said first group of external storage devices and a host, wherein
said first external storage control device is connected to a second external storage control device which is connected to a second group of external storage devices;
said first external storage control device being equipped with a storing means that stores write data transferred by a write command from the host and means that transfers the write data stored in said storing means to the second external storage control device according to a write command;
the first external storage control device also having means for storing the write data to both an external storage device belonging to said first group of external storage devices and to an external storage device belonging to said second group of external storage devices; and
wherein in case where said first external storage control device has received plural write commands for said data from the host, said first external storage control device transfers said write data to said second external storage control device by selecting a transfer method with the shortest processing time.
7. A first external storage control device according to claim 6, wherein said data transfer is performed according to a format stored in said storing means.
8. The system according to claim 6, wherein the first external storage control device is connected to the first group of external storage devices via an optical fiber cable.
9. A first external storage control device which is connected to a first group of external storage devices and to a second external storage control device, and which controls data transfer between said external storage devices and a host, wherein,
the second external storage control device is connected to a second group of external storage devices, and controls data transfer between said second group of external storage devices and the host,
said first external storage control device being equipped with a storing means that stores write data transferred through a write command from the host, a first transfer means to transfer write data to said second external storage control device for each of plural write commands received from the host, a second transfer means which transfers write data from the host to the second external storage control device for each of plural write commands received from the host by using only one write command,
the first external storage control device also including means for calculating processing time for data transfer between said first external storage control device and said second external storage control device using said first transfer means and using said second transfer means, means to compare said two processing times and for storing the same data to an external storage devices belonging to said first and second group of external storage devices and when said first external storage control device has received plural write data commands from the host, the external storage control device transfers data from said first external storage control device to said second external storage control device, using a transfer means that brings smaller processing time according to the result of said comparing means.
10. A first external storage control device according to claim 9, wherein data transfer from said first external storage control device to said second external storage control device by one write command is performed in a unit having a track length.
11. A first external storage control device according to claim 9, wherein said data transfer is performed according to a format stored in said storing means.
12. A first external storage control device according to claim 9, wherein said first external storage control device issues a write command brought from the host to said second external storage control device in case where said second external storage control device is not equipped with means to transfer write data of plural write commands by using only one write command.
13. A first external storage control device which is connected to a first group of external storage devices and to a second external storage control device, and controls data transfer between said first group of external storage devices and the host, wherein,
the second external storage control device is connected to a second group of external storage devices, and controls data transfer between said second group of external storage devices and the host,
said first external storage control device comprising:
a storing means that stores data which is transferred between the host and said second external storage control device;
a first transfer means for transferring data to said second external storage control device for each command received from the host;
a second transfer means for transferring data sent from the host by plural commands to said second external storage control device by using a single command;
means for calculating processing times for data transfer between said first external storage control device and said second external storage control device using said first and second transfer means; and
means for comparing said processing times.
14. A first external storage control device according to claim 13, wherein when storing the same data to external storage devices belonging to said first and second group of external storage devices, said external storage control device transfers data from said first external storage control device to said second external storage control device using a transfer means that has a smaller processing time according to a result of said comparing means, when said first external storage control device has received plural write data commands from the host.
15. A first external storage control device according to claim 14, wherein data transfer between said first external storage control device and said second external storage control device according to a single command is performed in a unit with a track length.
16. A first external storage control device according to claim 14, wherein said data transfer is performed according to a format in which the data is stored in said storing means.
17. A first external storage control device according to claim 13, wherein when an external storage control device which has received plural read commands, from the host, for the data which exists in said storing means in said second external storage control device and does not exist in said first group of external storage devices nor in said storing means in said first external storage control device, said external storage control device transfers said data from said second external storage control device to said first external storage control device, using a transfer means that has a smaller processing time according to a result of said comparing means.
18. A first external storage control device according to claim 17, wherein data transfer between said first external storage control device and said second external storage control device according to a single command is performed in a unit with a track length.
19. A first external storage control device according to claim 17, wherein said data transfer is performed according to a format in which the data is stored in said storing means.
20. A data transfer method in which data is transferred between a first external storage control device, which is connected to a first group of external storage devices and controls data transfer between said first group of external storage devices and a host, and a second external storage control device, which is connected to a second group of external storage devices and controls data transfer between said second group of external storage devices and the host, comprising the steps of:
storing the same data to external storage devices belonging to said first and second group of external storage devices, when said first external storage control device has received plural write data commands from the host,
wherein said first external storage control device performs the steps of
storing write data transferred by said plural write commands from the host to storing means;
comparing a time for transferring write data received by said plural write commands to the second external storage control device by one write command, with a time for transferring write data received by said plural write commands to the second external storage control device with each command as received; and
transferring the data from said first external storage control device to said second external storage control device, using a transfer means that has a smaller time for transferring write data according to a result of said step of comparing.
21. The data transfer method according to claim 20, wherein data transfer from said first external storage control device to said second external storage control device by one write command is performed in a unit having a track length.
22. The data transfer method according to claim 21, wherein said data transfer is performed according to a format in which the data is stored in said storing means.
23. The data transfer method according to claim 20, wherein the first external storage control device is connected to the first group of external storage devices via an optical fiber cable.
24. The system comprising:
a host processor;
a plurality of external storage devices connected to the host processor; and
means for transferring data from the host processor to one of said plurality of external storage devices by comparing a first transfer time for sending an entire track of data and a second transfer time for sending a specified number of individual records,
wherein the calculation of the first and second transfer times includes a determination of command chain time for sending data from the host processor and receiving a response from said one of said plurality of external storage devices,
wherein said means for transferring data transfers data according to a shorter of the first and second transfer times; and
wherein the plurality of external storage devices are connected to the host processor via optical fiber cables.
25. The system comprising:
a host processor;
an external storage device connected to the host processor; and
means for transferring data from the host processor to said external storage device by comparing a first transfer time resulting from sending an entire track of data and a second transfer time resulting from sending a specified number of individual records,
wherein the calculation of the first and second transfer time includes a determination of command chain time for sending data from the host processor and receiving a response from said external storage device,
wherein said means for transferring data transfers data according to a shorter of the first and second transfer times; and
wherein the external storage device is connected to the host processor via an optical fiber cable.
Description
FIELD OF THE INVENTION

The present invention relates to an external storage control device which stores data to an external storage device according to a write command from a host. In particular, the present invention relates to a system in which the same data is copied to another external storage device.

BACKGROUND OF THE INVENTION

When data used in a host are stored to plural external storage devices, main and sub external storage devices that hold the same data are sometimes provided under individual external storage control devices. In this case, these external storage control devices are mutually connected, and the main external storage control device issues a write command to the external storage control device which controls sub external storage devices when the external storage control device which controls main external storage devices receives a write command. Thus, data stored in the main and sub external storage devices are duplicated.

U.S. Pat. No. 5,155,845 discloses a method in which an external storage control device which controls main external storage devices and one which controls sub external storage devices are mutually connected. A main external storage control device which has received a write command from a host, transfers data to a sub external storage control device. Thus, the write process is performed in parallel for both of main and sub external storage devices.

SUMMARY OF THE INVENTION

When a host handles data stored in external storage devices with CKD (count, key, data) format as used in large scale computer systems, the host issues channel commands in succession for instructing data transfer of each individual record. Thus, each individual record undergoes the same command chaining sequence in order to be transferred.

FIG. 3 illustrates a case of plural records being written using the same command chaining sequence. This Figure illustrates the case in which plural records are written in succession by a single command-chaining. In an external storage sub-system having main and sub external storage devices that hold the same data, located under individual external storage control devices, when a channel device that is a host issues a command-chain (DEFINE EXTENT/LOCATE RECORD/WRITE(R1)/WRITE(R2)/WRITE(R3)) to write 3 successive records R1, R2, and R3 to a disk storage device that is under a main external storage control device, data flow between the channel device and the main external storage control device and between the main external storage control device and the sub external storage control device are shown in the processing sequences of FIG. 3. Thus, several command-chains between the main and sub external storage control devices for each data transfer of write records is executed.

Further, in case data is duplicated by adopting the system described above, the distance between main and sub external storage control devices becomes large considering the backups necessary in case of a disaster. Thus, an optical fiber cable is adopted as the interface cable. Accordingly, the influence of cable delay, which is considered to be constant for a metal cable, with respect to command-chaining time cannot be ignored. However, since this duplication is for back up purposes, the influence of the write process for the sub external storage control device during an ordinary process must be minimized.

In a case where the write command must be executed a number of times in accordance with the command-chaining described above, this command-chaining time required for writing to sub external storage control devices cannot be ignored. This is because the amount of command-chaining between main and sub external storage control devices increases. As a result, backup processing can severely decrease the throughput rate in ordinary processing.

Thus, one purpose of the present invention is to optimize the write process time for the sub external storage control device by taking into consideration the command-chaining time between main and sub external storage control devices. As a result, the present invention offers a means for achieving excellent performance even under the conditions explained above.

In order to achieve the above-mentioned purpose, the external storage control device according to present invention is equipped with a means for estimating command-chaining time between main and sub external storage control devices. There is also provided a means for estimating the time for a write process to a sub external storage control device before starting the write process to the sub external storage control device. The command is issued to the main external storage control device from the host. The present invention also includes means to select the best suited command-chaining method. Thus, a comparison is made between the above-mentioned estimated time with the data processing time required in the case of transferring data for a write record or data of plural tracks including a write record in one operation using a specified command. The present invention also includes command means for writing said data in a single operation.

It is possible for an external storage device to learn of the command-chaining time mentioned above by either measuring the command-chaining time from a specified command to the next command, or by setting the length of interface cable between main and sub external storage control devices from outside in advance. On the other hand, the time required for a write process for the sub external storage control device can be calculated by the above-mentioned information and by the information included in the command issued to the main external storage control device. Namely, command-chaining used for data input/output includes at least two specific channel commands prior the command to start data transfer. For example, for an external storage control device, the commands, "DEFINE EXTENT" and "LOCATE RECORD", are issued prior to data transfer, and the number of records to be processed and the data length are given, so that the amount of data to be transferred can be calculated.

Furthermore, the command-chaining time between main and sub external storage control devices depends upon length of interface cable and the performance of the external storage control device, and does not depend on commands made before and after the command-chaining. Accordingly, command-chaining time during data transfer can be estimated by measuring the time for two command chains. Also, the length of interface cable between main and sub external storage control devices, and support functions of a given external storage control device are known at the time of installation of a backup system. Thus, command-chaining time can be estimated with the length of interface cable as established.

Since the command-chaining time can be estimated as mentioned above, the processing time can also be estimated for a given amount of data transfer in the case that the command-chaining command from the channel device is issued to the sub external storage control device. Consequently, by comparing this processing time with a processing time in the case of transferring data for a write record, or, data of plural tracks including a write record together, using a command and command means to write said data at once, the best suited command-chaining instruction can be issued to the sub external storage control device.

Also, the external storage control device according to present invention is equipped with means to confirm that the object data exists in the data buffer of another external storage control device in order to transfer data from the data buffer within the external storage control device to an external storage control device that receives the write commands, in addition to data transfer means as mentioned above. Moreover, the processing time can be further reduced by transferring all the physical data together, including the control byte and the check byte in the data buffer.

Additionally, in case where object data for the read command, received from the host, exists in the buffer of an external storage control device other than the external storage control device which has received the read command, the processing time for performing a read-out can be shortened by transferring these data to the external storage control device which received the read command instead of accessing the other external storage device.

These and other objects, features and advantages of the present invention will become more apparent in view of the following detailed description of the preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a configuration of the data processing system according to an embodiment of the present invention.

FIG. 2 illustrates a configuration of the main disk control device according to an embodiment of the present invention.

FIG. 3 illustrates the data flow between the channel device, that is a host, the main disk control device, and the sub disk control device.

FIG. 4 illustrates the data flow in the case that data are transferred between the main and sub disk control devices record by record or in an entire track.

FIG. 5 illustrates data format in the data buffer of a disk control device for the case of 8 records per track.

FIG. 6 illustrates a graph showing the relation between number of records transferred and the processing time.

FIG. 7 illustrates a flow chart representing steps followed according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The preferred embodiments of the present invention will now be described in conjunction with the Figures. FIG. 1 illustrates a configuration diagram of a data processing system according to an embodiment of the present invention. This data processing system includes a main memory device 1, a channel device 2, a backup system 6 and a channel device 7. This data processing system also includes a main disk control device 3 equipped with a buffer memory 4, and a main disk storage device 5, and also includes a sub disk control device 8 equipped with a buffer memory 9, and a sub disk storage device 4. The channel device 2 is connected to the main disk storage control device 3 through an interface cable 11, the main disk storage control device 3 is connected to the sub disk storage control device 8 through an interface cable 12. Interface cables are also used to interconnect other elements shown in this Figure. Preferably, optical fiber cables are used as the interface cables.

As shown in FIG. 2 the main disk control device 3 includes a channel command analyzing section 31, a command judging section for judging commands to be issued to the sub disk control device 32, a management information table for the sub disk control device 33, a timer 34, a command issuing section for the sub disk control device 35, and a section for interpreting cable length and the function of the sub disk control device 36. Function blocks 31 33, 35 36 are realized by a micro-program executed by a microprocessor contained in the disk control device 3. Timer 34 is a hardware counter that is counted up according to a constant period. The sub disk control device 8 is constructed similarly to main disk control device 3.

The command-chaining time required between main and sub external storage control devices is measured in the main disk control device 3, by using the timer 34, the section for issuing command to the sub disk control device 35, and the section for interpreting cable length and function of the sub disk control device 36. Then, the command chaining time, Tsg, is measured when a command is processed once a pair of main and sub disk storage devices are established. The measuring is performed by timer 34 and is stored in the management information table 33 in the main disk control device 3.

The main disk control device obtains support function level information of the sub disk control device when the pair of main and sub disk storage device is established. This function level information is stored in the management information table of the main disk control device. This stored information is used to judge whether a write command to write data for write record, or, data of plural tracks including the write record can be accepted by sub disk storage control device or not.

If command judgment section for the sub disk control device 32 has judged from the support function level information that a specified command is not acceptable, when a write command is received from the channel device 2, the section for issuing command to the sub disk control device 35 unconditionally issues a command-chain sent from the channel device to the sub disk control device. Thus, the system is rendered more versatile in that it can connect even with a conventional device that does not support these functions.

The channel command analyzing section 2 operates as follows. When the channel device 2 issues a write command to the main disk control device 3, the channel command analyzing section 31 determines whether or not the write command is for a disk storage device that forms a pair with the main disk control device 3.

FIG. 6 is a graph illustrating command-chaining time for two separate cases. One case corresponds to the processing time required for transfer of data for one track including a write record. The information from the management information table for the sub disk control device 33 is used, as is the number of transfer records of LOCATE command, the number N which is analyzed by the channel command analyzing section 31, and average record length, L. Here, the straight line (I) can be explained by an equation as shown below using known values of command chaining time Tsg between the main and sub external storage control devices, the above analysis, and the data transfer velocity V between the main and sub external storage control devices 3 and 8.

Ts=NL/V+(N-1)Tsg                                           (1)

The straight line (II) shows the transfer time Ts', which is a constant value, for the case where data of one track is transferred together and where each record length is L, and number of records in a track is Na. Ts' can be represented by the following formula.

Ts'=NaL/V+Tsg                                              (2)

In the case of the sloped line (I), as the number of records increases, the processing time increases. At some point, i.e. for some number of records, it is faster to send the entire track of data, because the command chaining time Tsg is too great.

The section for judging commands to be issued to the sub disk control device 32 judges whether to issue the command chain to the sub disk control device as received from the channel device or to transfer data of one track all together based upon the information contained in FIG. 6, in view of the number of records N.

FIGS. 5 and 6 illustrate a case in which six records are to be written in a track that holds eight records of data. As seen from FIG. 4, transferring data of one track all together requires less processing time if the number of records is greater than 4. FIG. 6 also illustrates such a relationship according to the intersection of lines I and II. Command issuing section 35 issues the best suited command-chain to the sub disk control device 8, in view of all of the considerations mentioned above and according to the instruction of command judgment section 32.

FIG. 3 illustrates command chaining between a CPU (channel device or host) and a sub disk controller via a main disk controller. As shown, a number of commands have to be sent back and forth before a record (R1) can be transmitted. The same sequences is followed for subsequent records.

According to the present invention, write processing time to a sub disk storage device, i.e. back-up processing time, can be minimized by selecting a command-chain method to be issued to the sub disk control device. This is accomplished by comparing processing time for the case of issuing the command chain to the sub disk control device as received from the channel device with that of the case of transferring data for a write record, or, data of plural tracks including a write record all together.

FIG. 7 illustrates the flow of steps according to the present invention. First, the amount of data that is to be sent is calculated (STEP 100), i.e. the number of records. Then a time T1 is calculated (STEP 110). T1 is equal to Ts using equation (1) above, and is computed for the case of sending individual records. Then, a time T is calculated (STEP 120). T2 is equal to Ts' using equation (2) above, and is computed for the case of sending the entire track of data. In decision block 130, it is determined if T1>T2 (STEP 140). If so, then the entire track of data is sent (STEP 140). If not, then the individual records are sent separately (STEP 150). This process is repeated as necessary.

Although the present invention has been described above in connection with the preferred embodiments, one of ordinary skill in the art would be enabled by this disclosure to make various modifications to the preferred embodiments and still be within the scope and spirit of the present invention as embodied in the appended claims.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US5155845 *Jun 15, 1990Oct 13, 1992Storage Technology CorporationData storage system for providing redundant copies of data on different disk drives
US5247665 *Sep 28, 1989Sep 21, 1993Kabushiki Kaisha ToshibaData base processing apparatus using relational operation processing
US5572699 *Mar 15, 1993Nov 5, 1996Hitachi, Ltd.Variable length data in a parallel disk array
US5588012 *Dec 17, 1992Dec 24, 1996Fujitsu LimitedApparatus and method for ensuring data in external storage system
US5625840 *Apr 13, 1995Apr 29, 1997International Business Machines CorporationProgrammable external storage control apparatus
US5644787 *Aug 2, 1994Jul 1, 1997Seiko Epson CorporationApparatus for controlling data transfer between external interfaces through buffer memory using table data having transfer start address transfer count and unit selection parameter
US5740465 *Apr 7, 1993Apr 14, 1998Hitachi, Ltd.Array disk controller for grouping host commands into a single virtual host command
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US6529976 *Jun 15, 2000Mar 4, 2003Hitachi, Ltd.Heterogeneous computer system, heterogeneous input output system and data back-up method for the systems
US6647476Dec 22, 2000Nov 11, 2003Hitachi, Ltd.Subsystem replacement method
US6721841Dec 24, 2002Apr 13, 2004Hitachi, Ltd.Heterogeneous computer system, heterogeneous input/output system and data back-up method for the systems
US6871255Sep 17, 2003Mar 22, 2005Hitachi, Ltd.Heterogeneous computer system, heterogeneous input/output system and data back-up method for the systems
US6892268Sep 17, 2003May 10, 2005Hitachi, Ltd.Heterogeneous computer system, heterogeneous input/output system and data back-up method for the systems
US6922729 *Jul 30, 1999Jul 26, 2005International Business Machines CorporationMulti-connection control system
US6950917Mar 7, 2003Sep 27, 2005Hitachi, Ltd.Subsystem replacement method
US7051121Apr 25, 2003May 23, 2006Hitachi, Ltd.Method for controlling storage system, and storage control apparatus
US7080202Dec 10, 2004Jul 18, 2006Hitachi, Ltd.Remote storage disk control device with function to transfer commands to remote storage devices
US7082506Mar 8, 2002Jul 25, 2006Hitachi, Ltd.Remote copy control method, storage sub-system with the method, and large area data storage system using them
US7114049Sep 12, 2003Sep 26, 2006Hitachi, Ltd.Adaptive remote copy in a heterogeneous environment
US7130941Sep 15, 2003Oct 31, 2006Hitachi, Ltd.Changing-over and connecting a first path, wherein hostscontinue accessing an old disk using a second path, and the second path of the old disk to a newly connected disk via a switch
US7139888Oct 25, 2004Nov 21, 2006Hitachi, Ltd.Data processing system
US7143252Sep 5, 2003Nov 28, 2006Hitachi, Ltd.Storage apparatus system and method of data backup
US7155587Jan 11, 2005Dec 26, 2006Hitachi, Ltd.Storage subsystem and performance tuning method
US7165163Mar 22, 2005Jan 16, 2007Hitachi, Ltd.Remote storage disk control device and method for controlling the same
US7167962Dec 30, 2005Jan 23, 2007Hitachi, Ltd.Remote copy for a storage controller with reduced data size
US7177991Aug 8, 2003Feb 13, 2007Hitachi, Ltd.Installation method of new storage system into a computer system
US7184378Apr 20, 2004Feb 27, 2007Hitachi, Ltd.Storage system and controlling method thereof, and device and recording medium in storage system
US7194590Sep 12, 2003Mar 20, 2007Hitachi, Ltd.Three data center adaptive remote copy
US7200727Feb 4, 2005Apr 3, 2007Hitachi, Ltd.Remote storage disk control device with function to transfer commands to remote storage devices
US7200729Jun 30, 2005Apr 3, 2007Hitachi, Ltd.Subsystem replacement method
US7203806Apr 8, 2004Apr 10, 2007Hitachi, Ltd.Remote storage disk control device with function to transfer commands to remote storage devices
US7209986Jun 13, 2005Apr 24, 2007Hitachi, Ltd.Method for controlling storage system, and storage control apparatus
US7213114Aug 12, 2004May 1, 2007Hitachi, Ltd.Remote copy for a storage controller in a heterogeneous environment
US7219201Dec 30, 2003May 15, 2007Hitachi, Ltd.Remote storage disk control device and method for controlling the same
US7231465Sep 12, 2003Jun 12, 2007Hitachi, Ltd.Storage system, and method for controlling the same
US7231466Jun 15, 2006Jun 12, 2007Hitachi, Ltd.Data migration method for disk apparatus
US7246214Aug 4, 2004Jul 17, 2007Hitachi, Ltd.Remote copy for a storage controller with reduced data size
US7249234Apr 25, 2006Jul 24, 2007Hitachi, Ltd.Storage system and storage control device
US7263593Sep 15, 2003Aug 28, 2007Hitachi, Ltd.Virtualization controller and data transfer control method
US7290103May 11, 2006Oct 30, 2007Hitachi, Ltd.Data processing system
US7363446Mar 22, 2007Apr 22, 2008Hitachi, Ltd.Storage system and storage control device
US7363461Jul 26, 2006Apr 22, 2008Hitachi, Ltd.Remote storage disk control device and method for controlling the same
US7366853Jun 30, 2004Apr 29, 2008Hitachi, Ltd.Virtualization controller and data transfer control method
US7373670Feb 27, 2004May 13, 2008Hitachi, Ltd.Method and apparatus for setting access restriction information
US7380032Oct 26, 2005May 27, 2008Hitachi, Ltd.Storage system, and method for controlling the same
US7412543Jan 25, 2006Aug 12, 2008Hitachi, Ltd.Method for controlling storage system, and storage control apparatus
US7421549Mar 2, 2004Sep 2, 2008Hitachi, Ltd.Method and apparatus of remote copy for multiple storage subsystems
US7430648Feb 16, 2007Sep 30, 2008Hitachi, Ltd.Remote storage disk control device with function to transfer commands to remote storage devices
US7457899Jan 25, 2006Nov 25, 2008Hitachi, Ltd.Method for controlling storage system, and storage control apparatus
US7493466Jun 21, 2006Feb 17, 2009Hitachi, Ltd.Virtualization system for virtualizing disks drives of a disk array system
US7565502Jun 22, 2007Jul 21, 2009Hitachi, Ltd.System managing a plurality of virtual volumes and a virtual volume management method for the system
US7624241Nov 9, 2006Nov 24, 2009Hitachi, Ltd.Storage subsystem and performance tuning method
US7634588Mar 5, 2007Dec 15, 2009Hitachi, Ltd.Data migration method for disk apparatus
US7673107Jul 3, 2007Mar 2, 2010Hitachi, Ltd.Storage system and storage control device
US7694104Mar 19, 2007Apr 6, 2010Hitachi, Ltd.Virtualization controller and data transfer control method
US7707377Feb 20, 2008Apr 27, 2010Hitachi, Ltd.Remote storage disk control device and method for controlling the same
US7809906May 28, 2004Oct 5, 2010Hitachi, Ltd.Device for performance tuning in a system
US7818473Aug 11, 2008Oct 19, 2010International Business Machines CorporationEmbedded locate records for device command word processing
US7840767Jun 3, 2009Nov 23, 2010Hitachi, Ltd.System managing a plurality of virtual volumes and a virtual volume management method for the system
US7877568Apr 13, 2006Jan 25, 2011Hitachi, Ltd.Virtualization controller and data transfer control method
US7937513Oct 27, 2008May 3, 2011Hitachi, Ltd.Method for controlling storage system, and storage control apparatus
US7975116Mar 10, 2010Jul 5, 2011Hitachi, Ltd.Remote storage disk control device and method for controlling the same
US8046554Aug 27, 2010Oct 25, 2011Hitachi, Ltd.Storage subsystem and performance tuning method
US8055816Apr 9, 2009Nov 8, 2011Micron Technology, Inc.Memory controllers, memory systems, solid state drives and methods for processing a number of commands
US8078848Jan 9, 2009Dec 13, 2011Micron Technology, Inc.Memory controller having front end and back end channels for modifying commands
US8122214Oct 20, 2010Feb 21, 2012Hitachi, Ltd.System managing a plurality of virtual volumes and a virtual volume management method for the system
US8156561Sep 15, 2005Apr 10, 2012Hitachi, Ltd.Method and apparatus for setting access restriction information
US8190852Mar 19, 2007May 29, 2012Hitachi, Ltd.Virtualization controller and data transfer control method
US8255652May 17, 2011Aug 28, 2012Hitachi, Ltd.Remote storage disk control device and method for controlling the same
US8260973Sep 23, 2011Sep 4, 2012Micron Technology, Inc.Memory controllers, memory systems, solid state drives and methods for processing a number of commands
US8281098Sep 20, 2011Oct 2, 2012Hitachi, Ltd.Storage subsystem and performance tuning method
US8396995Aug 30, 2012Mar 12, 2013Micron Technology, Inc.Memory controllers, memory systems, solid state drives and methods for processing a number of commands
US8572352May 22, 2012Oct 29, 2013Hitachi, Ltd.Virtualization controller and data transfer control method
US8751700Mar 12, 2013Jun 10, 2014Micron Technology, Inc.Memory controllers, memory systems, solid state drives and methods for processing a number of commands
US8806657Mar 21, 2012Aug 12, 2014Hitachi, Ltd.Method and apparatus for setting access restriction information
US8843715Jan 27, 2012Sep 23, 2014Hitachi, Ltd.System managing a plurality of virtual volumes and a virtual volume management method for the system
US8966231Oct 11, 2011Feb 24, 2015Micron Technology, Inc.Modifying commands
USRE43600Jul 9, 2003Aug 21, 2012Hitachi, Ltd.External storage control device and data transfer method between external storage control devices
Classifications
U.S. Classification711/163, 711/100, 711/101, 711/1, 714/805
International ClassificationG06F3/06, G06F12/16, G06F13/10, G06F13/12
Cooperative ClassificationG06F2003/0692, G06F3/0613, G06F3/067, G06F3/0659, G06F2003/0697, G06F3/065, G06F3/0689, G06F3/0601
European ClassificationG06F3/06A4T6, G06F3/06A2P4, G06F3/06A4H4, G06F3/06A, G06F3/06A6L4R, G06F3/06A6D
Legal Events
DateCodeEventDescription
Mar 30, 2011FPAYFee payment
Year of fee payment: 12
Apr 30, 2007FPAYFee payment
Year of fee payment: 8
May 21, 2003REMIMaintenance fee reminder mailed
Apr 28, 2003FPAYFee payment
Year of fee payment: 4
Jun 3, 1999ASAssignment
Owner name: HITACHI, LTD., JAPAN
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OZAWA, KOJI;SANO, KAZUHIDE;KOIDE, TAKESHI;AND OTHERS;REEL/FRAME:009992/0903
Effective date: 19970107